I'm coming late to this thread, but I just wanted to point out one historical fact. The saffron color that we think of today in saffron kilts is a very muddy yellow color. However, the saffron color of the leinte of the sixteenth century, that the saffron kilts are supposedly inspired by, was actually a much brighter yellow -- what you might call a canary yellow.

This Dutch water color from 1574 shows the color fairly accurately.


There is also a good article on the saffron coloring at the Reconstructing History web site:
http://www.reconstructinghistory.com/irish/saffron.html

Aye,
Matt